Feline Diabetes Melliuts Flashcards
What’s the most common form of diabetes in the cat?
type II
Does gestational diabetes happen in cats?
not reported yet; has been reported in dogs
What are some risk factors for feline diabetes mellitus?
- age
- gender (Male > female)
- obesity
- indoor
- inactivity
- prolonged/ repeated steroids/ megestrol acetate
Which genetic mutation is shared between people and cats with diabetes mellitus?
melanocortin 4 receptor gene (Mc4R)
What are the 2 key features of type 2 diabetes mellitus?
- insulin resistance/ decreased sensitivity
- for every 1kg gain = 30% decrease in insulin sensitivity - decreased insulin secretion
- amylin/ islet amyloid polypeptide deposition
- chronic inflammation
- oxidative damage
Define impaired fasting glucose and impaired glucose tolerance.
Impaired fasting glucose:
= fasting glucose 6.5-10mmol/L
Impaired glucose tolerance (50% dextrose IV)
= glucose >9.9mmol/L (@ 2h with 0.5mg/kg glucose), or
= glucose > 6.5mmol/L (@ 3h with 1mg/kg)
Both conditions = prediabetic
At what glycemic level is the cat considered diabetic?
resting glucose > 10mmol/L
What resting glucose level is considered prediabetic in a cat?
if it’s below the renal threshold (14-16mmol/L), then glucosuria won’t be present
but is still considered prediabetic of glucose >10mmol/L
What are some signs of DKA?
- anorexia
- vomiting
- depression
Is plasma beta-hydroxybutyrate a reliable marker to differentiate between stress glycemia and diabetes?
No, if blood glucose <20mmol/L, beta-hydroxybutyrate is unlikely going to be increased
What does fructosamine concentration mean in cats?
likely reflective of the glycemic control in the preceding week. Only glucose >33mmol/L is likely to have a significance
Does have fructosamine = diabetes in cats?
No, if blood glucose is <20mmol/L, should still consider serial blood glucose check, glucosuria, and clinical signs
What’s the likelihood of relapse once in diabetic remissions? what’s the chance of a 2nd remission?
- 25-30% will relapse
- <25% will have a 2nd remission
What’s the treatment goal for diabetic cats that still have not achieved remission after 6m of treatment?
improving/ resolving clinical signs without inducing hypoglycemia
What are some known factors that can influence remission rate?
- older age (better)
- aiming for tight glycemic control
- recent glucocorticoid usage
- glucose <16mmol/L after insulin
- using long acting insulin (glargine, detemir)
- low carb diet
- lower maximum dose of insulin (glargine dose <0.4U/kg or 3IU/cat)
- absence of neuropathy
- lower cholesterol concentration
What’s the goal for blood glucose concentration for newly diagnosed diabetic cat?
- achieving normal to near normal glucose level (4 to <10mmol/L) while avoiding hypoglycemia
- increases likelihood of going into diabetic remission (2-4 weeks of euglycemia without treatments)
What are the 4 types of insulin used in cats, in order of preference?
- Glargine, long acting, less potent than lente
- Detemir, long acting, less experience in usage
- PZI, intermediate acting
- Lente, intermediate acting, patient would still have 2 hyperglycemic episodes/ day
Can glargine be diluted?
NO!
What’s the safest way to administer insulin <2units?
dosing pen
What’s the most important risk factor in feline diabetes mellitus?
Obesity
What’s the role of diet in preventing and managing feline diabetes mellitus?
low carb high protein = key in prevention/ remission
- important to make sure cat is in ideal body condition
- watch for concurrent CKD and diet needs – need to avoid high protein/ phosphorus
What’s the role of oral hypoglycemics? How do they work?
- good for pre-diabetic or use in conjunction with insulin
- not recommended as sole therapy for newly diagnosed DM cats unless the alternative is euthanasia
- works by stimulating insulin secretion from pancreas
- decrease GI glucose absorption
- or increasing insulin sensitivity in tissues
What are the 6 classes of oral hypoglycemics?
- sulfonylurea
- meglitinides
- biguanide
- thiazolidinedione
- alpha-glucosidase inhibitors
- trace elements
What’s the MOA of sulnoylurea?
It binds to ATPase, allowing for blockage of K+ efflux and opening of Ca2+ channel, thus promoting insulin exocytosis
- can be combined with meglitinides for greater efficacy
ex. glipizide
What’s the MOA of meglitinides?
Similar to sulfonylurea, but binds at a different site on the ATPase.
- can be combined with sulfonylurea for greater efficacy
ex. nateglinide
What’s the MOA of biguanides?
- increases tissue insulin sensitivity (hepatic and peripheral tissue)
- interrupts mitochondrial oxidative process
- corrects Ca2+ imbalance in peripheral tissues
ex. metformin
What’s the MOA of thizolidnedione?
improved insulin sensitivity in muscle, fat, and liver
ex. darglitozone
What’s the MOA of alpha-glucosidase inhibitors?
inhibits brush border disaccharidase breakdown of glucose, therefore leading to slowed down absorption/ less of a peak glucose absorption
- only works well after first 12h, not great for ones eating multiple times a day
- if already on a low carb diet, may not change much. Could be useful in cats needing renal diet
ex. acarbose
What are some trace elements that can help with glycemic control?
chromium, vanadium, and tungsten
What are some examples of emerging therapies for feline DM?
- incretin-based therapy.
Incretin is released after a meal. It stimulated insulin secretion and suppressed glucagon secretion
- ex. glucagon-like peptide 1 (GLP-1), enzymatically degraded by DPP-4
- example of drugs = GLP-1 agonist that are resistant to DPP-4, or DPP-4 antagonist - Amylin, co-secreted with insulin
Suppressed glucagon secretion, delays gastric emptying and promotes satiety - Smart insulin
long lasting insulin responsive to hyperglycemia. Only activated when hyperglycemia is present. Pending clinical trials
When should underlying disease be considered in terms of glycemia level?
Insulin dose >1-1.5U/kg VID, and BG >15mmol/L
What is the most common underlying disease causing insulin resistance in cats?
acromegaly
How does acromegaly lead to insulin resistance?
Acromegaly –> increases growth hormone production –> interferes with post-receptor insulin function
- also stimulates release of IGF-1, which has anabolic effects
- c/s = PU/PD/PP, weight gain
How is acromegaly treated?
Sx, RT, pasireotide
How does hyperadrenocorticism lead to insulin resistance?
glucocorticoids impair insulin sensitivity, decrease glucose tissue uptake in peripheral tissues, stimulates liver gluconeogenesis and may inhibit insulin secretion from beta cells
What’s the prevalence of DM in HAC cats?
80%
How does pancreatitis lead to insulin resistance?
It can directly destroy and pancreatic beta cells –> less insulin produced, loss of function, and reduced tissue sensitivity
What other treatment options are there for diabetic cats with chronic pancreatitis?
Could consider budesonide, cyclosporine, or chlorambucil
What’s threshold for hypoglycemia in cats?
2.8mmol/L
What are some clinical signs of hypoglycemia in cats?
- lethargy
- trembling
- depression
- ataxia
- seizure
- coma
How should hypoglycemia be managed?
- corn syrup
- dextrose infusion
- glucagon
- will need to reduce insulin dose by 25-50%, once hyperglycemia is reached again
